<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link rel="stylesheet" href="css/app.css" />
  </head>
  <body>
    <header>
      <div class="menu">
        <ul>
          <li>
            <a href="">首页</a>
            <a href="">电视</a>
            <a href="">手机</a>
          </li>
        </ul>
      </div>
    </header>

    <main>
      <div></div>
    </main>
  </body>
</html>
